Apparatus, system and method for mechanical, selective plant removal in mature and establishing crops including turfgrasses

ABSTRACT

An apparatus for applying a desired amount of mechanical abrasion to plants and selective cutting of undesirable plant material is provided. The apparatus includes a base, a brush and an elevation device for maintaining the base at desirable height. The base has a first longitudinal axis and a plurality of grooves, the grooves being oriented approximately perpendicular to the first longitudinal axis. The brush has a second longitudinal axis and a plurality of bristles and/or blades extending outwardly from the second longitudinal axis. The brush is attached to the apparatus such that the second longitudinal axis is substantially parallel to the first longitudinal axis and the brush is rotatable about the second longitudinal axis. The brush is spaced from the base such that the plurality of bristles engage the plurality of grooves. The base is adjustable enabling the operator to move the base closer or further from the rotating brush/blades.

RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §120 to U.S.Provisional Patent Application No. 61/929,607, filed Jan. 21, 2014, toU.S. patent application Ser. No. 14/601,574, filed Jan. 21, 2015, U.S.patent application Ser. No. U.S. 15/487,867 filed Apr. 7, 2017, U.S.patent application Ser. No. U.S. 15/482,119 filed Apr. 7, 2017, and U.S.Provisional Application 62/322,938 filed Apr. 15, 2016, the entiredisclosures of which are incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to an apparatus useful in reducing weedpressure and/or improving wear tolerance in crops. For example, anapparatus, system and method is provided to improve turfgrass quality,wear tolerance, reduce weed pressure, and for retaining more turfgrasscover when a turfgrass area is subjected to traffic.

BACKGROUND OF THE INVENTION

As used herein, the term “crop” refers to desirable plants, including,in one aspect of the invention, turfgrasses. Turfgrasses are differentfrom other grasses in three primary ways: turfgrasses can form a densecontiguous community, tolerate frequent mowing and tolerate traffic. Dueto these unique qualities turfgrasses are used extensively in our urbanculture including golf courses, athletic fields, parks, cemeteries,roadsides and home lawns. Proper turfgrass management is critical to itslong-term sustainability and the safety of the playing surfaces whereit's utilized. Turfgrass is managed according to five primary culturalpractices; 1) mowing, 2) fertilization, 3) cultivation, 4) irrigationand 5) pest control.

While turfgrasses are often grown as part of an athletic field, golfcourses and/or lawns, other types of grasses may also comprise adesirable crop plant. For example, grasses may be grown for grazing bycattle. Such grasses may comprise forage grasses, turfgrasses, or acombination thereof. Another example of a crop that may also be grownfor harvest is hay.

Pest control employs preventative and/or curative approaches toprotecting desirable crop species, such as grasses, from potentiallydamaging weeds, insects, and/or diseases. Traditionally, turfgrassmanagers have implemented an Integrated Pest Management (IPM) program tomaintain pest populations below threshold levels. The IPM approachallows the judicious use of pesticides to maintain pest populations atan acceptable level to maintain a healthy turfgrass stand. A pesticideis a broad term used to describe any substance that prevents, destroys,repels or mitigates any pest. Pesticides are further categorizedaccording to their intended targets (i.e. herbicides, fungicides,insecticides, etc.). Herbicides, pesticides targeting weeds only,accounted for the highest usage of pesticides in the home and gardensector with 66 million pounds applied in 2007 (U.S. EnvironmentalProtection Agency, Pesticides Industry Sales and Usage 2006 and 2007Market Estimates).

The concern regarding pesticide applications has increased tremendously,particularly where there is potential risk of exposure to children suchas lawn areas, athletic fields and parks/playgrounds. The primaryconcern regarding low, nonacute, repetitive and combined exposures areincreased risk of cancer, abnormal neurodevelopment, asthma,perturbation of gestational growth, and endocrine-mimicking effects (USAAP 2012 and Can Fam Phys, 2007). J. R. Roberts, C. J. Karr, PesticideExposure in Children, Pediatrics Vol. 130, No. 6 (2012); K. L. Bassil,et al, Cancer Health Effects of Pesticides, Canadian Family Physician,Vol. 53 (2007). These very serious concerns have resulted in pesticiderestrictions related to athletic fields in 41 out of 50 states,according to the Sports Turf Managers Association. Connecticut hasbanned all pesticide applications on school grounds and athletic fieldsserving grades pre-k through grade 8. There is discussion to expand thescope of this law to high school and public grounds. The state of NewYork passed the Childs Safe Playing Field Act that essentially banspesticide use on schools grounds, day care centers and athletic fieldsthrough grade 12. Additionally, several municipalities across the U.S.have banned pesticides on parks, open space parcels and public rights ofway. This includes 7 states, 18 cities, and 92 parks/playgrounds.Concerns regarding pesticide impacts on human health and the environmenthave even advanced to the university and college level where somecampuses or specific areas of campus have been declared pesticide-freeas they embrace more sustainable approaches.

Turfgrass breeding efforts have resulted in improved cultivars ofdifferent turfgrass species that have better insect and diseaseresistance helping to reduce the susceptibility of some turfgrassspecies. Additionally, entomopathogenic nematodes have been shown tobiologically control some of the most damaging root feeding insects.See, Georgis, R., and R. Gaugler, Predictability in biological controlusing entomopathogenic nematodes. J. Econ. Entomol. 84(3):p. 713-720.However, a consistent method of weed control is not available. Thisleaves many high quality turfgrass areas susceptible to weedinfestations on a perennial basis. This is particularly a concern inhigh traffic areas such as athletic fields where turfgrass cover iscontinually reduced and opportunistic weeds are able to germinate,develop quickly, and potentially dominate a turfgrass stand in a veryshort period of time.

Previous research has investigated the effects of utilizing existingequipment such as spring-tine harrows or vertical cutting units todamage weeds and create a competitive advantage for turfgrasses onfootball pitches (Larsen, S. V., P. Kristoffersen, and J. Fischer,Turfgrass management and weed control without pesticides on footballpitches in Denmark. Pest Manage. Sci. 60(6):p. 579-587). However, thesemethods were thought to be too injurious to the established turfgrassresulting in modest weed control and sometimes increased weed pressure.

Research has shown that perennial broadleaf weeds and annual grassyweeds are less traffic tolerant than desirable turfgrass species.Miller, N. A., and J. J. Henderson 2012, Organic management practices onathletic fields: Part 1: The effects on color, quality, cover, and weedpopulations. Crop Sci. 52(2):p. 890-903 and J. T Brosnan et al, LargeCrabgrass, White Clover, and Hybrid Bermudagrass Athletic Field PlayingQuality in Response to Simulated Traffic, Crop. Sci. 54:1838-1843(2014). Therefore, when intense traffic is applied over time to aturfgrass stand containing perennial broadleaf weeds and annual grassyweeds, the desirable turfgrasses persist and the weeds do not. Trafficis a combination of wear (i.e. tearing and bruising of leaf tissue) andsoil compaction (i.e. forcing soil solids closer together). Research hasalso indicated that when traffic components (wear and compaction) areimplemented separately to different areas and their detrimental effectsare compared, wear is more detrimental to the quality of vegetativecover than compaction. See, Dest, W. M., J. S. Ebdon, and K. Guillard,Differentiating between the influence of wear and soil compaction andtheir interaction of turfgrass stress, Int. Turfgrass Soc. Res. J. 11(Part 2) p. 1067-1083.

Weeds substantially reduce the aesthetic quality of turfgrass stands,but most importantly are less traffic tolerant than turfgrasses.Therefore, once weeds dominate an existing turfgrass stand, weeds areunable to persist under the constant traffic and vegetative cover isdrastically reduced. Athletic fields with reduced vegetative cover havebeen linked to higher surface hardness values and increased risk ofsurface related injuries. See, Dest, W. M., and J. S. Ebdon. Study:Natural turf use levels. SportsTurf. 27(5) p. 8, 10-11 and Brosnan etal. 2014. However, chemical applications, such as selective herbicides,are more likely to be limited on athletic fields due to human exposureconcerns.

Accordingly, there is a need for an apparatus, system and method ofgrowing and improving desirable, wear-tolerant plants and reducingundesirable weeds that may compete with this growth. There is further aneed for an apparatus, system and method of reducing weeds in turfgrassand other crops without the application of selective herbicides. Thereis also a need for an apparatus, system and method of producing improvedwear tolerance in turfgrass.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an apparatus, systemand method of growing and improving crops (including turfgrasses) andreducing weeds that may compete with this growth and improve weartolerance.

In one example of the present invention, an apparatus for applying adesired amount of mechanical abrasion and selective pulling and/orcutting to a crop is provided. The apparatus includes a base, a brushand an elevation device for maintaining the base at desirable height.The base has a first longitudinal axis, a plurality of grooves, and aplurality of cutting disks. The grooves and cutting disks are orientedapproximately perpendicular to the first longitudinal axis.Additionally, the disks may be disposed on a counter rotating rollerthat is located on a leading edge of the base. The disks may vary indiameter, some serrated for cutting plant material and others texturedfor lifting prostrate plant material, or a combination thereof. Thebrush has a second longitudinal axis and a plurality of bristles and/orblades extending outwardly from the second longitudinal axis.

The brush is attached to the apparatus such that the second longitudinalaxis is substantially parallel to the first longitudinal axis and thebrush is rotatable about the second longitudinal axis. The brush isspaced from the base such that the plurality of bristles engage theplurality of grooves and disks. The brush and the roller with disks maybe configured to rotate in opposite directions. The base is adjustableenabling the operator to move the base closer or further from therotating brush/blades.

The elevation device is configured to support the base above the groundbut in contact with the crop. The elevation device may comprise any oneof several structures, including vertically-adjustable rollers, wheels,skids, and combinations thereof. For example, the elevation device maysupport the base such that crops and other plants such as weeds areengaged by the plurality of bristles/blades and drawn into the pluralityof grooves and/or teeth and/or vertically orientated rotating disks.

In one example, the brush is cylindrical. In another example, rows ofbristles may be arranged in a helix. The plurality of bristles willtypically exceed the plurality of grooves and/or vertically orientatedrotating disks. Also, the bristles are typically smaller in diameterthan the width of the grooves and/or vertically orientated rotatingdisks. The brush may include longer, softer bristles on a leadingportion of the brush and shorter, more aggressive bristles on a trailingportion of the brush.

The grooves may have a constant width or a tapered width, and may betextured to increase wear. The base may comprise a single, integratedunit or a combination of a base blade mounted on a blade holder, wherethe grooves are formed on the base blade.

In another example of the present invention, an apparatus is providedhaving a base having a powered roller having a first longitudinal axis,where at least one auger disposed on the powered roller. A brush havinga second longitudinal axis and a plurality of bristles extendingoutwardly from the second longitudinal axis, the brush being a rotatablymounted such that the second longitudinal axis is substantially parallelto the first longitudinal axis and the brush is rotatable about thesecond longitudinal axis. The brush is spaced from the base and thepowered roller such that the plurality of bristles engage the at leastone auger. The apparatus may further include an elevation device tomaintain the base at a height above the surface such that the plants areengaged by the at least one auger and the plurality of bristles. Thepowered roller and the brush may counter rotate. There may be aplurality of augers, and there may be cutting disks disposed between theaugers.

A method of applying a desired amount of mechanical abrasion todesirable plants and undesirable plants is also presented. The methodincludes periodically applying mechanical abrasion to the desirableplants and the undesirable plants, wherein the level of mechanicalabrasion is selected to be damaging to the undesirable plants andsubstantially within the wear tolerance of the desirable plants. Thedesirable plants may include turfgrasses and/or forage grasses. Themechanical abrasion may be applied by a rotating cylindrical brush withbristles engaging a base having a plurality of grooves. In one example,the period of applying mechanical abrasion is about once per week.However, the period of application will vary depending on weed pressure,growing conditions, maturity of the desirable plants, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention aredescribed with reference to the following drawings. In the drawings,like reference numerals refer to like parts throughout the variousfigures unless otherwise specified.

FIG. 1 illustrates a font view of an apparatus according to one exampleof the present invention, the apparatus being attached to a conventionalmower;

FIG. 2 is an enlarged view of a portion of the apparatus of FIG. 1;

FIG. 3 is a rear view of the apparatus of FIG. 1;

FIG. 4 is a view of a base blade and blade holder of the apparatus ofFIG. 1.

FIG. 5 is an alternate view of a base blade and blade holder of theapparatus of FIG. 1.

FIG. 6 illustrates an additional implementation of a base bladeincluding grooves and one or more cutting disks oriented perpendicularto the base blade according to the present invention.

FIG. 7 illustrates a second additional implementation of a base bladeincluding auger shaped grooves oriented toward one or more cutting disksaccording to the present invention.

FIG. 8 illustrates an additional implementation of a brush, roller anddisks according to certain aspects of the present invention.

DESCRIPTION OF THE EMBODIMENTS

While the invention has been described in detail with respect to thepreferred embodiments thereof, it will be appreciated that upon readingand understanding of the foregoing, certain variations to the preferredembodiments will become apparent, which variations are nonethelesswithin the spirit and scope of the invention.

The terms “a” or “an”, as used herein, are defined as one or more thanone. The term “plurality”, as used herein, is defined as two or as morethan two. The term “another”, as used herein, is defined as at least asecond or more. The terms “including” and/or “having”, as used herein,are defined as comprising (i.e., open language). The term “coupled”, asused herein, is defined as connected, although not necessarily directly,and not necessarily mechanically. The term “or” as used herein is to beinterpreted as an inclusive or meaning any one or any combination.

Reference throughout this document to “some embodiments”, “oneembodiment”, “certain embodiments”, and “an embodiment” or similar termsmeans that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the present invention. Thus, the appearances of such phrases or invarious places throughout this specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments without limitation.

The drawings featured in the figures are provided for the purposes ofillustrating some embodiments of the present invention, and are not tobe considered as limitation thereto. Term “means” preceding a presentparticiple of an operation indicates a desired function for which thereis one or more embodiments, i.e., one or more methods, devices, orapparatuses for achieving the desired function and that one skilled inthe art could select from these or their equivalent in view of thedisclosure herein and use of the term “means” is not intended to belimiting.

As used herein, the term “crop” refers to desirable plants, includingdesirable grasses, including, but not limited to Kentucky bluegrass,perennial ryegrass and combinations thereof, forage grasses, hay, etc.The term “weed” refers to undesirable perennial, biennial and/or annualplants, including broadleaf (dicotyledonous) and grassy(monocotyledonous) species. As used herein the term “traffic” refers toa combination of wear (i.e. tearing and bruising of leaf tissue) andsoil compaction (i.e. forcing soil solids closer together) of theturfgrass. As used herein the term “wear tolerance” refers to theability of plants, including but not limited to desirable grasses, towithstand aggregate, repeated stresses of damage to above ground plantmaterial over a period of time.

As is illustrated in the accompanying FIGS. 1-4, an example of thepresent invention is generally shown as apparatus 100 for operating ondesirable turfgrasses and undesirable weeds. In particular, the presentinvention provides an apparatus, system and method of reducing weedpressure on desirable turfgrasses. Apparatus 100 has a cylindrical brush110; a grooved base 120 and a roller 130 (FIG. 3). Roller 130 is anelevation device, may be configured to be adjustable in a verticaldirection 140 to control the height of the base 120. In FIG. 1, theapparatus 100 is illustrated as being used in conjunction with a ride onmower 160, which may provide power to rotate the cylindrical brush 110and propel the apparatus 100 across a surface, such as a an athleticfield.

Referring to FIG. 1 the cylindrical brush 110 may be configured, forexample in a width of approximately 70 cm and have a 17 cm diameter. Thecylindrical brush 110 may be comprised of a plurality of separate rows.In the example illustrated in FIGS. 1-3, four rows 112 of brushes areused, each being installed on an axle with a 90 degree twist to form ahelix. Other numbers of rows may also be used with appropriateadjustments in the amount of twist on each row of brushes. Each row 112can be comprised of a plurality of nylon bristles 111 each beingapproximately 1.5 mm diameter and having a 5 cm pile height. Differingpile heights may also be included. For example, the bristles may beselected or trimmed such that a leading portion of bristles engage thegrooves coming appreciably closer to the bottom of the groove than thetrailing portion but do not contact the bottoms of the grooves, whilethe trailing portion of the bristles are shorter providing moreclearance to the bottom of the groove.

In one illustrated example, bristles 111 are the same size, however,bristles of varying diameters may be included in brush 110. For example,referring to another example of a brush 210 in FIG. 8, bristles 211 amay be softer and longer than bristles 211 b. Bristles 211 a may beincluded on a leading portion of brush 210, and bristles 211 b may beincluded on a trailing portion of brush 210. The longer, softer bristles211 a help divert desirable turfgrass leaf blades away from the moreaggressive, stiffer bristles 211 b. Bristle tips may be cut or rounded.

To further optimize the level of mechanical wear, the bristles may besmooth, textured or micro notched in the vertical or horizontal plane.In cases where weeds are especially hardy, metal blades may also beincluded on the brush 110. The blades may be shorter than the bristles,and the bristles would help bring the weeds into engagement with thebase blade. While a plurality of staples of flexible bristles are apreferred example of a brush, the terms “brush” and “bristles” as usedherein may also include any protrusions (e.g., tines, nubs) configuredto impart selective tearing and/or bruising of leaf tissue.

The rows 112 are mounted on a shaft 113, which is supported by bearingson either end of apparatus 100. The rows 112 of the bristles 111 can beconfigured in a helicoid (a spiral shape around an axis or cylinder).The arrangement of the bristles 111 and rows 112 allow vegetation orplant material to enter the apparatus 100 and be subjected to therotating bristles 111. The bristles 111 force the plant material intogrooves 121 of the base 120. The grooves 121 of the base 120 aredesigned to: 1) assist the bristles/blades to grasp the undesirableplants and completely remove the plants from the ground (including theroots), 2) increase pressure on the leaf tissue/stem to promote tearingand bruising from bristle action and/or 3) completely remove the leaffrom the stem. Repeated applications at key points during the growingseason exhausts the carbohydrate reserves of the undesirable plants,leading to plant death.

Finally, roller 130 provides variable height of operation and maintainsa desired height 140 of the base 120 during operation. Other elevationdevices may also be used, including wheels, skids, segmented rollers,and combinations thereof. It is preferable, but not necessarilyrequired, for the elevation device to include a mechanism for adjustingthe height of the base.

This apparatus can have multiple configurations to implement this methodof weed control. Configuration examples are as follows; Stand-aloneconfigurations include self-propelled walk-behind and ride-on units. Theapparatus 100 can be used concurrently with a mower (i.e. two separatepieces of equipment operated independently) (not shown) or as anintegrated part configured as a mower attachment, mounted in front,mid-section or rear of an existing mower. This includes ganged units,self-powered pull-behind units, and power take off driven, three pointhitch mounted or pull-type units for tractors. Alternatively, theintegrated part can be designed integral as part of the mower or mowerdeck. In this embodiment, the frame of the apparatus is configured tohold the cylindrical, brush 110 enabling the brush 110 and bristles 111to rotate and interact with the grooved base 120 so as to impart wear onplant material, such as weeds and turfgrasses. In one example of theinvention, the brush rotates. In other examples, the brush may engage ina reciprocating motion. As illustrated in FIG. 1, a belt 115 may drive apulley 116 which is attached to the shaft 113. Alternatively, the shaft113 may be driven hydraulically. The shaft 113 may also be driven bywheels through a gearset as is known with reel-type mowers.

FIG. 2 illustrates a view of how the bristles 111 interact with thegrooves 121. The bristles have a diameter which is smaller than theopening of the grooves, so the bristles may pass through the grooveswithout binding or popping out of the grooves. However, the bristles 111are not precisely aligned with the grooves 121, and enter the grooves atslight angles to the grooves. The bristles 111 consequently rub alongthe sidewalls 122 of the grooves 121 and/or top edges of the grooves.One or more bristles 111 enter the grooves 121 in a semi-loose statewith the plants such as a weed species and/or turfgrass. As the bristles111 and the smaller weeds (containing leaflets) progress through thegrooves 121, the bristles 111 damage leaves and/or stems of undesirablebroadleaf plants by abrading them against the sidewalls 122 of thegrooves 121 and/or bottom of the grooves 121. For weed species withbroader leaf morphology, the action of the bristles 111, grooves 121,and vertically oriented cutting disks will interact to tear, bruise andselectively cut leaf tissue. Some weed species may be completely removedfrom the soil. For example, crabgrasses have been observed to be engagedby the bristles and grooves and be uprooted. However, thinner grassleaves experience less abrasion from the apparatus 100 and are moretolerant of abrasion. In this respect, the mechanical abrasion of thepresent invention is not the same as mowing (which cuts all plantsequally) or vertical mowing (a cultivation procedure that is damaging toturfgrass). The vertically-oriented cutting disks are designed toselectively cut the plants with broader leaf morphology. In one example,grooves 121 can be configured to have a depth of 6 mm. In anotherexample, the depth of the grooves 121 increases and/or decreases as thebristles move through the grooves 121.

The base 120 containing grooves 121 can be configured so that the firstportion is a lip 123, for example, approximately 3 cm. Preferably, lip123 is smooth, so that desirable crops may slide off the base afterbeing engaged by the bristles. In a first example, the grooves 121 havea uniform width. In a second example, the grooves 121 taper from a widthof 8 mm to a width of 4 mm. The grooves may be formed when casting thebase 120, by cutting notches into base 120, by welding fins onto base120, or by other methods. The grooves 121 may be various widths andlengths, so long as they cooperate with the brush 110 to applymechanical wear to plants. In another example, the sidewalls of thegrooves may be sharpened or serrated to increase mechanical tearing andto selectively cut plants with morphologies appreciably different thanthe desirable crop plants. In another example, the base 120 may includecounter-rotation slicing disks interspersed between and parallel withthe grooves 121. The slicing disks spin in the opposite direction (i.e.counter rotate) as the brush 110 to damage weed leaves, selectively cut,and/or pull weeds out of the soil.

Referring to FIG. 8, a roller 200 may be fitted to the front of the base220. The roller is powered to rotate in a direction counter to the brush210. The roller may include textured disks 224 and serrated disks 226.The serrations may be optimized for selective cutting of undesirableplants. The textured disks, which may be spaced apart 3.0 inches, arelarger and help lift prostate plants into engagement with the brush 210and grooves 221 (FIG. 6) of the counter rotating roller and of the base220 (FIG. 8). The textured disks are in line with sidewalls 122 (FIG. 2)of the grooves of the base blade 120. Smaller diameter disks 222 (FIG.6) are between the textured disks and are in line (parallel) with thegrooves of the base blade providing grooves 221 and acting as theleading edge of the base blade designed to remove, by pulling, cutting,and/or tearing, weeds more aggressively than the fixed grooves on thebase blade or textured disks. One or more serrated disks 226 may beinterspersed between the textured disks 224.

A blade guard 228 may be fitted underneath and partially around eachserrated disk to prevent the serrated disk from ripping or tearingdesirable grasses. The blade guards divert the turfgrass leaf bladesaway from the serrated disks 226. Referring to FIG. 6, an example of aroller 200 a including both textured disks and serrated, cutting disksis illustrated. Referring to FIG. 7, another example of a roller 200 bmay include augers 230 to move plant material toward cutting blades andprovide a twisting action to grab and pull the weeds tighter than thedesirable crop. The augers 230 and disks 226 may be arranged in variouscombinations. In another example of a roller, the augers may extendacross the entire roller without any cutting disks.

In the illustrated example, the base 120 comprises a base blade 120 a,which contains the grooves 121, and a blade holder 125, on which thebase blade 120 a is mounted. This allows base blade 120 a to be replacedif necessary, without replacing the entire base. In another example, thebase 120 is a unitary structure with the grooves 121 integrally formedthereon. In another example, the base may be concave, so that thebristles maintain a consistent distance from the grooves. In anotherexample, roller 200 may be substituted for rounded lip 123. An axle ofthe roller (200 a or 200 b) may be configured to perform the samefunction as rounded lip 123.

A prototype has been developed, and results from trials show thatroutine use on established turfgrass stands creates an environmentfavorable for obtaining results of desirable turfgrasses stands anddetrimental to the most troublesome weed species in cool-seasonturfgrasses.

A first study involved the use of the apparatus on Kentucky bluegrass.This is the predominate species utilized on athletic fields and homelawn mixtures where cool-season grasses are utilized. The study includedthree treatments: 1) Weed Defoliator/Extractor once per week, 2)chemical herbicide, and 3) an untreated control, with two replications.Clover populations were evaluated qualitatively utilizing a scale of0-100% weed cover, prior to treatment applications. Plots were treatedwith the Weed Defoliator/Extractor and mowed immediately following,simulating the Weed Defoliator/Extractor device being incorporated intoa mower deck. Plots were qualitatively assessed six weeks laterfollowing seven treatments with the Weed Defoliator/Extractor device.Percent clover control was calculated using the Henderson-Tilton formulawhich utilizes pretreatment weed populations, post treatment weedpopulations and weed populations in the untreated control. Analysis ofvariance was used to test for significant (P≤0.05) differences betweentreatments. Mean separations were conducted using Fisher's leastsignificant difference test with a 0.05 probability level. Treatmentswith the same letter are not significantly different. The apparatus ofthe present invention successfully controlled over 70% of the clover(significantly more than the untreated control). The chemical weedcontrol treatment was applied after the last rating date to maximizeefficacy. However, the efficacy of the chemical treatment will likely be100%.

A second study was conducted on perennial ryegrass and was designed tolook more closely at how to best utilize the Weed Defoliator/Extractordevice in terms of frequency. Perennial ryegrass is another speciesheavily utilized on athletic fields and in home lawn mixtures. The studyincluded six treatments; 1) Weed Defoliator/Extractor once per week, 2)Weed Defoliator/Extractor twice per week, 3) Weed Defoliator/Extractorbiweekly, 4) as needed, 5) chemical herbicide, and 6) untreated controlwith three replications. Clover populations were evaluated qualitativelyutilizing a scale of 0-100% weed cover, prior to treatment applications.Plots were treated with the Weed Defoliator/Extractor and mowedimmediately following. Plots were qualitatively assessed six weekslater. Percent clover control was calculated as described above. Theseresults show that Weed Defoliator/Extractor treatments applied once perweek were most effective for reducing the clover populations. Appliedonce per week, Weed Defoliator/Extractor treatments controlled over 98%of the clover (significantly more than the untreated control). Thechemical weed control treatment was applied after the last rating dateto maximize efficacy. However, the efficacy of the chemical treatmentwill likely be 100%.

The present invention produces an environment advantageous for themonocotyledonous morphology of desirable grasses by imposing a uniform,modest level of wear. The apparatus 100 is configured to provide minimaldisturbance to the existing grass stand and damage only the weeds.Additionally, this apparatus 100 does not disturb the soil surface,unlike spring-tine harrows or vertical cutting units of the prior artthat have disadvantages of exposing additional weed seed that canpotentially germinate and compete with the grass. The apparatus 100 canalso be used to manage weed populations in other turfgrass areas orcropping systems.

Accordingly, the method of the present invention creates an environmentwhere turfgrasses are able to persist and where weeds are not able topersist. For example, the morphology of broadleaf weeds makes them morevulnerable to the action of the apparatus of the present invention;whereas desirable turfgrasses are not unduly adversely affected. Leavesof weeds are much wider and often times more succulent than turfgrasses.The apparatus of the present invention, based on these morphologicaldifferences, damages weeds more than turfgrasses. The damaged weedsrequire regeneration, re-growing and/or rejuvenation thereby allowingthe less damaged turfgrasses to grow and thrive in the place of weeds.

More specifically, once the leaf tissue of the weed species is damagedits ability to absorb the suns energy to produce carbohydrates throughthe process of photosynthesis is greatly reduced or eliminated. As theapparatus 100 of the present invention is used, the weed leaf tissue isdamaged or removed with repeated and regular use. The weed will need torely on carbohydrate reserves in the root system for recovery andgrowth. This reserve supply will eventually be exhausted, leading toplant death.

In operation, the apparatus 100 can be used routinely with mowing. Theapparatus 100, nonetheless, can be employed separately as well as aself-propelled walk behind or ride on unit. In one embodiment theapparatus 100 is used concurrently with mowing such as, for example, asan integrated part configured as a mower attachment, mounted in front,mid-section or rear of an existing mower. This includes ganged units,self-powered pull-behind units, and power take off driven, three pointhitch mounted or pull-type units for tractors. Alternatively, theintegrated part can be designed integral as part of the existing ornewly designed mower deck.

Thus, according to the above description, the present inventive conceptmay be implemented in a number of ways. While certain configurations ofstructures have been illustrated for the purposes of presenting thebasic structures of the present invention, one of ordinary skill in theart will appreciate that other variations are possible which would stillfall within the scope of the appended claims. For example, the directionof rotation of the second longitudinal axis, orientation of the baseblade, variations in the geometries of the brush and its bristles and/orother protrusions to impart wear, depth and/or width of grooves and/orrotating vertically oriented slicing disks, spacing betweenbrushes/knives, number and dimension of bristles/knives andgrooves/rotating vertically oriented slicing disks and length of theaugered portion of the counter rotating roller are contemplated.Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

What is claimed is:
 1. An apparatus for applying a desired amount ofmechanical abrasion and for providing selective removal of plantsgrowing from a surface, comprising: a. a base having a firstlongitudinal axis and further comprising a plurality of grooves and aplurality of rotating disks, the grooves and rotating disks beingoriented approximately perpendicular to the first longitudinal axis; b.a brush having a second longitudinal axis and a plurality of bristlesextending outwardly from the second longitudinal axis, the brush beingrotatably mounted such that the second longitudinal axis issubstantially parallel to the first longitudinal axis and the brush isrotatable about the second longitudinal axis; and c. an elevation devicefor maintaining the base at a desired height above the surface and incontact with the plants; wherein the brush is spaced from the base suchthat the plurality of bristles engage the plurality of grooves and theplurality of rotating disks.
 2. The apparatus of claim 1, whereinelevation device maintains the base at a height such that the plants areengaged by the plurality of bristles and drawn into the plurality ofgrooves and plurality of rotating disks.
 3. The apparatus of claim 1,wherein the plurality of rotating disks are disposed on a rollerattached to a leading edge of the base.
 4. The apparatus of claim 3,wherein the roller and the brush counter rotate.
 5. The apparatus ofclaim 1, wherein the plurality of rotating disks comprise textureddisks.
 6. The apparatus of claim 1, wherein the plurality of rotatingdisks comprise cutting disks.
 7. The apparatus of claim 1, wherein theplurality of rotating disks comprise serrated cutting disks and whereinthe apparatus further comprises a guard located underneath and partiallyaround each cutting disk.
 8. The apparatus of claim 1, wherein the brushfurther includes a first plurality of bristles on a leading portion ofthe brush and a second plurality of bristles on a trailing portion ofthe brush, wherein the first plurality of bristles are softer and longerthan the second plurality of bristles.
 9. The apparatus of claim 1,wherein the brush has bristles with a pile height that is tapered suchthat only selected portions of the brush engage the bottoms of thegrooves.
 10. An apparatus for applying a desired amount of mechanicalabrasion and for providing selective removal of plants growing from asurface, comprising: a. a base having a powered roller having a firstlongitudinal axis and further comprising at least one auger disposed onthe powered roller; b. a brush having a second longitudinal axis and aplurality of bristles extending outwardly from the second longitudinalaxis, the brush being a rotatably mounted such that the secondlongitudinal axis is substantially parallel to the first longitudinalaxis and the brush is rotatable about the second longitudinal axis; andwherein the brush is spaced from the base and the powered roller suchthat the plurality of bristles engage the at least one auger.
 11. Theapparatus of claim 10, further comprising an elevation device tomaintain the base at a height above the surface such that the plants areengaged by the at least one auger and the plurality of bristles.
 12. Theapparatus of claim 10, wherein the powered roller and the brush counterrotate.
 13. The apparatus of claim 10, wherein the powered rollerfurther comprises a plurality of augers.
 14. The apparatus of claim 10,wherein the powered roller further comprises a plurality of augers and aplurality of cutting blades disposed between the augers.
 15. A apparatusfor selective removal of undesirable plants comprising: a. pulling meansfor applying selective mechanical pulling action on the undesirableplants, wherein the level of pulling action is selected to remove theundesirable plants and leave desirable plants substantially undamaged;and b. height means for adjusting a height of the wear means relative tothe desirable plants and the undesirable plants.
 16. The apparatus ofclaim 15, further comprising cutting means for applying cutting actionon the undesirable plants.